Orientationless internal closure/retainer and valve assembly employing same

ABSTRACT

A closure/retainer for the end of a tubular hollow having a plurality of engagement surfaces such as windows formed about the inner periphery. The closure/retainer has a plurality of locking fingers disposed thereabout, with the number, width and spacing of the fingers such that each window is engaged by at least one locking finger for any random rotary orientation of the closure/retainer. The closure/retainer is particularly suitable for automated axial assembly as for example in a fuel tank vapor vent valve for retaining the float in the tubular valve body.

BACKGROUND OF THE INVENTION

The present invention relates to closures or retainers for hollowchambers and particularly closures for tubular members where it isdesired to insert the closure member in an open end of the tubularmember for providing closure thereto and/or retaining other memberswithin the tubular member. In particular, the present invention relatesto retainers or closures for retaining a float operated valve in a valvebody having a float chamber such as for vapor vent valves forcontrolling flow of vapor in a fuel tank to a vent passage extendingexternally of the tank.

Heretofore, fuel tank vapor vent valves have employed a float operatedvalve for closing against a vent port upon movement of the float towardthe vent port from rising fuel level in the tank during refueling,sloshing or rollover of the vehicle. In known float operated fuel tankvapor vent valves, the float and valve are assembled into the floatchamber or hollow tubular portion of the valve body and a cap orretainer is inserted therein for retaining the float in the chamber.Typically, spring tabs or fingers are provided on the cap or closure forengagement with corresponding engagement or locking surfaces, such aswindows, formed in the tubular hollow upon insertion of the closuretherein. However, this arrangement has the disadvantage that the end capmust be properly oriented rotationally or in a circumferential directionduring insertion to insure that the fingers or tabs on the closureengage the locking or engagement surfaces provided in the valve body.This has been a disadvantage or drawback where it is desired to providefor automated insertion of the closure or end cap into the body. Whereit has been desired to automate such an assembly, it has been foundextremely costly and complex to provide both axial and rotary alignmentof the cap during the automated assembly.

Thus, it has long been desired to provide a way or means of assembling aclosure/retainer in a tubular hollow without the need for rotational orcircumferential orientation to insure engagement of the locking surfacesof the closure against the engagement surfaces provided in the tubularhollow.

BRIEF SUMMARY OF THE INVENTION

The present invention provides an rotationally orientationlessclosure/retainer for internal assembly in a hollow, particularly of theopen end of a tubular member. The closure/retainer is provided withretaining, or locking fingers or tabs which engage correspondingengagement surfaces, such as windows, formed in the circumferentialsurface of the tube or hollow. The engagement surfaces of the tubularhollow are of circumferential extension and spacing so as to permitengagement of at least one of the retaining fingers with each one of theengagement surfaces in the tubular hollow. The closure/retainer of thepresent invention may be inserted in the end of an open tubular memberand snap locked therein irrespective of the rotational orientation ofthe closure/retainer with respect to the tubular hollow and thus lendsitself readily to automated assembly.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a portion of a side elevation view of a tubular member ofemploying the present invention.

FIG. 2 is a cross section taken along section indicating lines 2—2 ofFIGS. 2, 1 and 3;

FIG. 3 is a section view taken along section indicating lines 3—3 ofFIG. 2;

FIG. 4 is a schematic of a portion of FIG. 3 showing the identificationof the various angular relationships of the locking fingers andengagement surfaces;

FIG. 5 is a cross section of a valve assembly employing the presentinvention;

FIG. 6 is a bottom view of the valve assembly FIG. 5.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIGS. 1 through 3, a closure/retainer assembly is indicatedgenerally at 10 and includes a tubular member or housing 12 having ahollow interior hollow 14. The periphery of a the hollow 14 has providedthereabout in circumferentially spaced arrangement a plurality ofengagement surfaces preferably comprising windows 16 the number, spacingand circumferential width thereof which will be hereinafter described ingreater detail.

A closure/retainer member 18 has a plurality of circumferentially spacedfingers or tabs 20 each provided with a locking or engagement surface 22on the tip thereof. Preferably surface 22 is tapered to provide acamming action upon axial assembly. The number, circumferential spacingand width or arcuate extension of the fingers 20 will be describedhereinafter in greater detail. The fingers 20 are configured so as to bedeflected inwardly by the surface 22 engaging the edge or end of themember 12 upon insertion of the closure 18 therein and elasticallyrebound or spring to move outwardly in a radial direction to engage theedge surface of the windows 16 adjacent the open end of the tubularmember 12. This engagement is illustrated in FIGS. 2 and 3.

Referring to FIG. 4, the arcuate extension or width of each of thewindows 16 is denoted by the reference character (γ) Gamma and thespacing between the windows denoted by the reference character (Δ)Delta. The fingers or tabs 20 each have an arcuate extension or widthdenoted by the reference character (α) Alpha and an arcuate spacingdenoted by the reference character (β) Beta.

Fingers 20 in windows for engagement surfaces 16 are arranged such thatfor a plurality N of the fingers 20 and a number K of the engagementsurfaces 16 the relationship of the number N with respect to K is setforth by the expression N=K (m+i) where m is an integer of at least 2and is the maximum number of fingers 20 engaged in each window 16; and,i is an integer of at least one and is the minimum number of fingerscontacting each space between the windows 16.

The central angle subtended by each of the engagement surfaces orwindows 16 is denoted by the reference character Gamma (γ) and isdetermined by the expression: γ=360°×m/N. The central angle Delta (Δ)subtended by the spacing between the engagement surfaces 16 isdetermined by the expression:Δ=360°(1/K−m/N)The central angle is determined by the expression:β=γ/m−αwhere α is the central angle subtended by the circumferential extent orwidth of each of the blocking fingers.

The relationship between α and β is determined from the expression:α+β=γ/m.

Thus, from the forgoing expressions it will be seen that for any chosenvalue of m, i and the engagement surface K, the corresponding number oflocking fingers N their width α and spacing β and engagement surfaceangle γ may be determined. This, aforesaid relationship insures thateach of the windows or engagement surfaces 16 will have at least one ofthe locking fingers 20 engaged therein for any random or rotationalorientation of the closure 18 with respect to the body 12 to therebypermit insertion and locking by axial movement only.

Referring to FIGS. 5 and 6, the invention is shown as embodied in thefloat operated fuel vapor vent valve indicated generally in 30 andhaving a body 32 with a float chamber 34 is a vent outlet port 36 formedin the upper end of the chamber for permitting fuel vapor to dischargeto a vent passage 38 exposed externally of the fuel tank. It will beunderstood that the valve body 32 includes a mounting flange 40 topermit the valve to be inserted from the exterior of the tank to anaccess opening therein and the flange subsequently secured to the tank,as for example by weldment. The chamber 34 has disposed therein a float42 which has a resilient valve member 44 retain thereon and which closesagainst port 36 upon the float being moved upwardly by rising fuel levelin the tank. The float 42 is retained in the lower end of the body 32 bya retainer or closure 46 which is made in accordance with the inventionand which has a plurality of radially outwardly extending fingers 48disposed thereon for engagement with corresponding engagement surfaces(not shown in FIG. 5) formed on the inner peripheral surface of the openend of the body 32. It will be understood that the arrangement, andwidth and spacing of the fingers 48 and engagement surfaces in theembodiment of FIGS. 5 and 6 is determined by the procedures set forthabove with respect to FIGS. 1 through 4.

The present invention thus provides for a closure/retainer for internalassembly in a tube or hollow chamber having a plurality of engagementsurfaces disposed there around with corresponding fingers provided onthe closure/retainer for engaging the engagement surfaces upon axialinsertion therein. The closure of the present invention provides for thespacing and circumferential width of the engagement surfaces and thefingers in such a manner that each of the engagement'surfaces has atleast one of the fingers engaged therein irrespective of the randomrotational orientation of the closure/retainer. The closure/retainer ofthe present invention thus permits automated assembly of a closure intothe end of a tubular member by axial movement only and without requiringany rotational orientation to insure engagement of the locking surfaces.The invention finds particular applications in the automated assembly ofa closure/retainer for the float in the body of a float operated fuelvapor vent valve.

Although the invention has hereinabove been described with respect tothe illustrated embodiments, it will be understood that the invention iscapable of modification and variation and is limited only by thefollowing claims.

1. An internally mounted closure assembly comprising: (a) a tubularmember with a plurality of K discrete windows, each window having anedge surface acting as an engagement surfaces, wherein said windows arecircumferentially spaced thereabout adjacent one end thereof; (b) a plugmember configured to interfit said one end and having a plurality of Nlocking fingers extending radially therefrom in circumferentially spacedarrangement wherein fix any circumferential orientation of the plugmember with respect to the tubular member, at least one of said lockingfingers engages each of said engagement surfaces, wherein each of saidlocking fingers is deflectable outwardly in the radial direction toengage the edge surface of each of said windows.
 2. The closure assemblydefined in claim 1, wherein N=K (m+i), where i is an integer of at leastone, m is the integer of at least two and the central angle γ subtendedby each engagement surface γ=360° m/N, the central angle Δ subtended bythe space between said engagement surface is${\Delta = {360{{^\circ}( {\frac{1}{K} - \frac{m}{N}} )}}},$the central angle subtended by the spacing β between the locking fingersis determined from β=γ/m−α, where α is the circumferential extent ofeach of the locking fingers.
 3. The closure assembly defined in claim 1,wherein said plug member has a generally cup-shaped configuration. 4.The closure assembly defined n claim 1, wherein said tubular member hasan annular shoulder formed therein and said plug is registeredthereagainst.
 5. The closure assembly defined in claim 1, wherein eachof said locking fingers engages one of said engagement surfaces in snaplocking engagement.
 6. The closure assembly defined in claim 1, each ofsaid plug members is formed of plastic material.
 7. The closure assemblydefined in claim 6, wherein said discrete engagement surfaces eachcomprises an edge of a window formed in said tubular member.
 8. Theclosure assembly of claim 1, wherein each of said locking fingers has atapered surface that cams the edge surface of each of said plurality ofwindows.
 9. A fuel vapor vent valve assembly comprising: (a) a valvebody adapted for installation in a fuel tank having a float chamber witha vent passage communicating with a vent outlet port and a generallytubular open end; (b) a float disposed in the float chamber and operableto close the vent port upon fuel rising to a certain level in the tank;(c) a retaining member received in said open end with a plurality of Ncircumferentially spaced fingers extending radially therefrom, whereinthe valve body has a plurality of K discrete windows, each window havingan edge surface acting as an engagement surface, in said valve body,wherein at least one of said fingers is engaged with each of saidengagement surfaces for any circumferential orientation of said cap withrespect to said body, and wherein each of said fingers is deflectableoutwardly in the radial direction to engage the edge surface of each ofsaid windows.
 10. The assembly defined in claim 9, wherein N=K (m+i),where i is an integer of at least one m is an integer of at least two,the central angle γ subtended by each engagement surface is$\gamma = {360{^\circ}\;\frac{m}{N}}$ the central angle Δ subtended bythe space between windows is${\Delta = {360{{^\circ}( {\frac{1}{K} - \frac{m}{N}} )}}},$the central angle subtended by the spacing β between the fingers isdetermined from $\beta = {\frac{\gamma}{m} - {\alpha.}}$ where α is thecircumferential extent of each of the locking fingers.
 11. The valveassembly defined in claim 9, wherein said body and plug are formed ofplastic material.
 12. The valve assembly defined in claim 9, whereinsaid fingers are elastically deflectable both inwardly and outwardly inthe radial direction.
 13. The valve assembly defined in claim 9, whereineach of said discrete engagement surfaces includes an edge of a windowformed in said body.
 14. The valve assembly defined in claim 9, whereineach of said fingers engages one of said engagement surfaces in snaplocking arrangement.
 15. The valve assembly defined in claim 9, whereinsaid body has an annular shoulder formed therein with said retainingmember registered against said shoulder.
 16. The valve assembly definedin claim 9, wherein said retaining member has a cup-shapedconfiguration.
 17. The closure assembly of claim 9, wherein each of saidfingers has a tapered surface that cams the edge surface of each of saidplurality of windows.
 18. A method of assembling a float operated valvecomprising: (a) providing a valve body with an open ended float chamber;having a vent port communicating with a vent outlet and a plurality ofwindows, each window having an edge surface acting as an engagementsurface; (b) disposing a float operated valve member in said chamber;and, (c) providing a plug with a plurality of circumferentially spacedfingers extending radially therefrom, wherein for any circumferentialorientation of the plug with respect to the valve body, at least one ofsaid fingers engages each of said engagement surfaces, and (d) insertingthe plug in random circumferential orientation and engaging each of saidengagement surfaces with at least one of said fingers by deflecting eachof said fingers outwardly in the radial direction to engage the edgesurface of each of said windows.
 19. The method defined in claim 18,wherein said step of inserting comprises inserting said plug only in anaxial direction.
 20. The method defined in claim 18, wherein said stepof engaging includes snap locking.